I’ve been struggling a lot with how much force my left hand (the fretting hand) should be applied when playing fast, and in general. I’ve heard many people say that using the lightest possible touch is best, but I’m not sure how to square that with really advanced famous people who seem to play really hard (Steve Vai, Guthrie Govan, etc.) To me it seems like these guys sometimes play very aggressively, so is it a matter of always maintaining a light touch with the fretting hand and using the picking hand to dictate power? Are the hands supposed to be decoupled like that? In my experience, when I start to play more aggressive, or when I’m nervous playing in front of other people, I start to really press down hard on the fretboard.
If it is the case that the lightest possible touch is best, what are you supposed to do for bends? Bending the sting requires a lot of force applied by your fretting hand, and I’ve observed a tendency in my own playing to maintain that force immediately afterward while playing regular fretted notes. But should I be focused on relaxing that tension immediately once the bend is over? I find that generally it’s really hard to let go of the tension in my index finger.